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Hudson River Fish Evolve To Cope With PCB Pollution

The Atlantic Tomcod; a species of bottom feeding fish; in the Hudson River, have quickly developed a gene that renders them immune to toxic PCB pollution, despite many other species of fish dying due to this exposure.

PCB's (Polychlorinated biphenyl ) is a extremely toxic chemical with many applications. Its main uses were as dielectric and coolant fluids in electrical apparatus, cutting fluids for machining operations, carbonless copy paper and in heat transfer fluids. PCB's are extremely dangerous for fish and even more dangerous for humans who eat contaminated fish.

General Electric released about 1.3 million pounds of PCB's in the Hudson river from 1947-1976. The Vast Hudson river was totally compromised with PCB's. To this day PCB's remain at a high level in the Hudson river because PCB's will get buried in the sediment and not break down.

Scientists looked at what happens to most vertebrates. All vertebrates have genes that code for receptors called AHR's (aryl hydrocarbon receptors). These receptor Proteins are in the cytoplasm of cells. When PCBs diffuse into cells, they connect to the AHR protein and are carried into the nucleus of the cell. In the nucleus, the receptor and toxin attach to the cell's DNA and turn on genes that shouldn't be activated. In basic terms when most fish embryos are exposed to PCB's it basically causes the fish to develop small hearts that do not beat properly this can lead to a many variant of problems and ultimately leads to the death of that particular fish. This is what would also happen to the fish in question; the Atlantic tomcod however progressively the Tomcod unlike any other fish had begun to flourish in the PCB rich waters and it got scientists thinking.

Scientists believe the Atlantic Tomcod had experienced natural selection, in which they developed a resistance towards PCB's. initially they were clueless on what actual adaptations had occurred. The fish still had the same visual characteristics as a normal Tomcod but somewhere in the genetics it had adapted to cope with PCB's.

In a mutated Atlantic Tomcod it was discovered that the AHR's (aryl hydrocarbon receptors) that theoretically should transport the PCB's to the nucleus of the cells will sense that it is a toxic Chemical and will not transport PCB's to the nucleus. This stops the chain reaction that causes toxic affects on this species of fish.

The mutation or adaptation involved in this evolutionary response is caused by the deletion of a six base pair that produces a protein two amino acids short of a receptor that is found on an unevolved Atlantic Tomcod. However no matter how small this mutation is its proven that other Tomcod are 100 times more likely to have negative effects from PCB pollution.

In most cases of evolution it is estimated to take millions and millions of year. This particular Evolutionary case is thought to have occurred rapidly over the span of no more than 60 years!

Its a fact this mutation helps the Tomcod thrive in PCB rich waters. But their will be negative consequences on other organisms trying to survive in this ecosystem. Since the Tomcod can withstand tedious amounts of PCB's with no negative effects. If another organism tries to eat the tomcod it will also be digesting all the PCB's stored in the Tomcods fat. The other organism will not have the same adaptation as the Tomcod so it renders them vulnerable to the deadly effects PCB's have on most organisms.

By Brendan Casola

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Summary of Information Researched And Learned in Class

For this article I had to research an abundance of information. I used scientific articles and studies to write this. I researched how PCB's can affect fish and what affect it has on the Tomcod. I researched what percent of this species of fish in that particular river were mutated. I researched what the mutations were, how quickly they came to be and what advantages/ disadvantages it has on the species and ecosystem. In Biology we learn about evolution and natural selection and species that are evolving currently. I took that topic and expanded on it with one particular example.

By Brendan Casola


Science: Scientists had to look at the genetic makeup of this evolved Tomcod and compare and contrast it to the genetic makeup of a regular Tomcod. Their were vast important scientific discoveries made by this occurrence.

Technology: The reasons these fish adapted to PCB's is because companies were dumping them in to the river. This disrupts an entire ecosystem and it is important to know for future reference to think about the environment before just worrying about technology.

Society: This rapid evolution of a species proves to science that evolution is not just something that occurs over millions of years but it could also occur in a shorter period of time. This in a way redefines the way people think and learn about evolution as a whole.

Environment: The dumping of PCB's in the Hudson river destroyed a thriving ecosystem and caused vast change in the environment. This evolution theoretically should never had occurred but because of the environmental damage General Electric was causing it forced a species of fish to adapt.

By Brendan Casola

Expert Interview in Human Evolution

Ian Tattersall, Phd

Ian Tattersall, PhD, is Curator in the Department of Anthropology at the American Museum of Natural History in New York. He is recognized as a leading scientist in the field of Human Evolution, with a career than spans several decades and countries around the world. Tattersall has authored many books, including Becoming Human: Evolution and Human Uniqueness, and is credited with a number of major exhibits at the AMNH, in particular the Hall of Human Biology and Evolution.

Interviewer: Before we begin, let the audience know what kind of education must be completed in order to be succesful in this field?

Tattersall: So for the degree level you'll need Bachelor's degree, masters and Phd for research and teaching. The degree field required evolutionary biologyor related life science.

Interviewer: What kind of experience is needed?

Tattersall: Well requirements vary from position and hiring agency

Interviewer: Key skills that you required to get in this position?

Tattersall: Obviously science skills,critical thinking,complex problem solving,mathematics,active learning,computers and writing are all things that you could benefit from.

Interviewer: This might be a little personal but what can we assume is your salary in this department?

Tattersall: I'm not ready to reveal this information but the average salary for all biological scientists is around 74.000$

Interviewer: What have been the most significant Fossil finds?

Tattersall: Well, the last two decades of the 20th century provided a huge number of extraordinary finds of extinct humans that have totally changed our perception of our evolutionary past.

Interviewer: Have finds like these complicated human evolution theories?

Tattersall: These findings have taughts us that human evolution is a matter of evolutionary experimentation rather than of a fine tuning within a lineage. Before we believed that Human evolution was a process of a lineage but this is not the case. Human evolution has proceeded in very much the same way as the evolution for mammals

Interviewer: Let's talk about Neanderthals

Tattersall: Well for a long time we thought the dominant process was linear, where a species gives rise to another. In this case we thought we evolved from Neanderthals but in fact they're so different from us that they could not possibly have been linear ancestors. They were our "co-lateral relatives".

Interviewer: When can we assume the human ape split occured?

Tattersall: About 7-8 million years ago

Interviewer: What do you see as the future of Human evolution?

Tattersall: To state the obvious it's still ongoing, and that we can look to the past to predict where our species is headed in the evolutionary future.

Interviewer: Thank you for your time and knowledge and information that you shared with us today!

Tattersall: Thanks for having me!

By Stefan Otovic


Event: The Power of Evolution

Starting December 15 there will be an amazing event happening at the science center. This event has been put together by the greatly respected Richard Dawkins, author of The God Delusion. The event will cover everything you need to know about evolution from key concepts to the nitty gritty must know facts. Evolution is the basis of life and how our species and all species alive right now got to this point, during the event you will be taught three big concepts of evolution; natural selection, reproductive barriers and continental drift. All three are very important parts of evolution and I’m excited to see how much you can learn.

Natural selection is a huge part of life, but what is it really. It’s when individuals with inherited characteristics well suited to the environment leave more offspring than those that aren’t. This would be clearly visible in today’s society but because of morality we have created medicines to prolong the life of people that were going to die. There are three types of selection, stabilizing selection, directional selection and disruptive selection. I heard from an inside source that Richard himself will be going over the pros and cons of natural selection and whether or not we should allow nature to take its course on the human race. These are all factors of life and understanding them is important, going to the event would allow just the ordinary person to create factual opinions on such topics.

Reproductive barriers are the prevention of similar species from interbreeding, in some cases like a female horse and a male donkey can have an offspring, but their offspring will be infertile. This part of the event will display several pairs of similar species and the barriers they face. For example the western spotted skunks breed in the fall while their close relative the eastern spotted skunk breeds in the late winter which means the two types of skunks will never be in the mood at the same time. This is an interesting part of the event and I hope everyone reading this goes to this part and absorbs as much knowledge as possible.

The last section is surprising continental drift, usually we hear continental drift in geography but it plays a key part in understanding evolution. Each continent is floating on a hot mantle and moving at two centimeters per year, proof of this is the matching Mesozoic fossils in West Africa and Brazil. During the presentation at the event they will cover how Australia has such unique organisms compared to the rest of the world, they drifter away from the huge mass of continents and the organisms evolved based on their environment. This is the part I’m personally most excited for and I can’t wait to see you all there.

This event will be super exciting and should be the number one event of the science center this decade, don’t risk not going and buy your tickets online right now.

By Owen Robinson

Movie review and Analysis of Summer Blockbuster Dawn of the planet of the apes

A decade after the annihilation of mankind from the ALZ-113 virus there is a group of survivors living off of rations in the city of San Francisco, Our what used to be cute ape Caesar is now the leader of a group of evolved apes. His son Blue Eyes was with his friend when they have run in with the group of surviving humans who are being lead by Malcolm, tension is high. Caesar is notified of the survivors and goes with an entourage to discuss peace because he doesn’t want war, but his second in command Koba hates the humans and deeply wants to wipe them out. Malcolm later comes to Caesar to discuss the necessary fixing of a dam that provides electricity for the city, Caesar allows it but Koba stages a situation that leads to war because the guy left in charge of the humans while Malcolm is fixing the dam gets all the humans armed with guns and this was the perfect storm for war.

Dawn of the Planet of the Apes was a great film, with thrilling and emotional scenes from the perspective of the apes and the humans. I enjoyed the action and the adventure that we had from the hut village of the apes to the run down buildings of the humans. The movie manages to capture your interest early on with the development of characters but they really capture the emotion when you understand that both sides are the same, man and beast. The one thing I didn't like was the cheesy fake newsreel montage at the beginning but besides that I would rate the movie eight out of ten.

This movie uses a strong form of natural selection where the human race is killed off by a virus until only the genetically strong are left. We have learned in class that humans continue to fight against natural selection but in this case nature takes its course. After most of the humans are killed off the evolved apes rise up using their newly learned intelligence to create a society amongst tribes of apes. I find this interesting but unrealistic because it’s cool to see what would theoretically happen if a virus killed off most of the human race. Overall I would recommend you sit down and watch this film with a bowl of popcorn and some salted nuts cause it's a wild ride.

By Owen Robinson

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Works Cited Including Pictures

Toxic river means rapid evolution for one fish species. (n.d.). Retrieved November 14, 2015, from http://evolution.berkeley.edu/evolibrary/news/110301_pcbresistantcod: (wrote article from Following sources):

Hansson, M. C., Wittzell, H., Persson, K., and von Schantz, T. (2004). Unprecedented genomic diversity of AhR1 and AhR2 genes in Atlantic salmon (Salmo salar L.). Aquatic Toxicology. 68: 219-232.

Revkin, A. C. (May 15, 2009). Dredging of pollutants begins in Hudson. The New York Times.
Retrieved March 8, 2011 from The New York Times.

Wirgin, I., Roy, N. K., Loftus, M., Chambers, R. C., Franks, D. G., and Hahn, M. E. (2011). Mechanistic basis of resistance to PCBs in Atlantic tomcod from the Hudson River. Sciencexpress. Epublication ahead of print, February 17, 2011.

By Anne Minard, for National Geographic News PUBLISHED Sat Feb 19 06:08:00 EST 2011. (n.d.). Hudson River Fish Evolve PCB Immunity. Retrieved November 14, 2015, fromhttp://news.nationalgeographic.com/news/2011/02/110217-hudson-river-pcb-fish-evolution-water/

(n.d.). Retrieved November 15, 2015, from http://evolution.berkeley.edu/evolibrary/images/news/pcbpath.gif

"Rediscovering Biology - Unit 9 Human Evolution: Rediscovering Biology - Unit 9 Human Evolution: N.p., n.d. Web. 15 Nov. 2015.

"How to Become an Evolutionary Biologist: Education and Career Roadmap." Study.com. N.p., n.d. Web. 15 Nov. 2015.

Panayiotou, Helen E. Biology Source 11. Pearson. Print.


Brendan Casola

Stefan Otovic(Editor also)

Owen Robinson